more inplace arithmatic tests

tests/run/inplace.pyx

@@ -160,3 +160,87 @@ def test_complex_inplace(double complex x, double complex y):
     x += y
     x *= y
     return x
+
+
+# The following is more subtle than one might expect.
+
+cdef struct Inner:
+    int x
+
+cdef struct Aa:
+    int value
+    Inner inner
+
+cdef struct NestedA:
+    Aa a
+
+cdef struct ArrayOfA:
+    Aa[10] a
+
+def nested_struct_assignment():
+    """
+    >>> nested_struct_assignment()
+    """
+    cdef NestedA nested
+    nested.a.value = 2
+    nested.a.value += 3
+    assert nested.a.value == 5
+    
+    nested.a.inner.x = 5
+    nested.a.inner.x += 10
+    assert nested.a.inner.x == 15
+
+def nested_array_assignment():
+    """
+    >>> nested_array_assignment()
+    c side effect 0
+    c side effect 1
+    """
+    cdef ArrayOfA array
+    array.a[0].value = 2
+    array.a[c_side_effect(0)].value += 3
+    assert array.a[0].value == 5
+    
+    array.a[1].inner.x = 5
+    array.a[c_side_effect(1)].inner.x += 10
+    assert array.a[1].inner.x == 15
+
+cdef class VerboseDict(object):
+    cdef name
+    cdef dict dict
+    def __init__(self, name, **kwds):
+        self.name = name
+        self.dict = kwds
+    def __getitem__(self, key):
+        print self.name, "__getitem__", key
+        return self.dict[key]
+    def __setitem__(self, key, value):
+        print self.name, "__setitem__", key, value
+        self.dict[key] = value
+    def __repr__(self):
+        return repr(self.name)
+
+def deref_and_increment(o, key):
+    """
+    >>> deref_and_increment({'a': 1}, 'a')
+    side effect a
+    >>> v = VerboseDict('v', a=10)
+    >>> deref_and_increment(v, 'a')
+    side effect a
+    v __getitem__ a
+    v __setitem__ a 11
+    """
+    o[side_effect(key)] += 1
+
+def double_deref_and_increment(o, key1, key2):
+    """
+    >>> v = VerboseDict('v', a=10)
+    >>> w = VerboseDict('w', vkey=v)
+    >>> double_deref_and_increment(w, 'vkey', 'a')
+    side effect vkey
+    w __getitem__ vkey
+    side effect a
+    v __getitem__ a
+    v __setitem__ a 11
+    """
+    o[side_effect(key1)][side_effect(key2)] += 1